Incandescing electric lamp



(NoMode l.) W Y T. A. EDISON.

INGA'NDESGING ELBGTRIG. LAMP. No. 264,655 Patented Sept. 19, 1882.

WITNESSES UNITED STATES PATENT OFFICE.

THOMAS A. EDISON, OF MENLO PARK, NEW JERSEY.

INCANDESCI'NG ELECTRIC LAMP.

SPEGIIIIGATION forming part of Letters Patent No. 264,655, datedSeptember 19, 1882.

I Application filed August 7, 1882. (No model.) Patented in EnglandSeptember 27,1881, No. 4,174: in Italy November 9, 1881;

in France December 5, 1881, No. 145,554; in Canada December 14, 1881,No. 13,835, and in India January 18, 1882,1lo. 74.

To all whom it may concern:

Be it known that I, THOMAS A. EDISON, of Menlo Park, in the county ofMiddlesex and State of New Jersey,have invented a new and usefulImprovement in Incandescing Electric Lamps, (Case No. 444;) and I dohereby declare that the following is a full and exact description of thesame, reference being had to the accompanying drawing, and to theletters of reference marked thereon.

In the use of incandescent electric lamps it is exceedingly convenientin some cases to have the leading-in wires of a lamp attached to theconductors in such a manner that they may be readily connected ordisconnected at will, in order that a lamp may be used in one place oranother, as desired. Such connecting and disconnecting of electricalconductors, however, produces a considerable spark, which in somelocations especially in mines, flouring-mills, powder-mills, or otherplaces where explosions are likely to occur-would be very dangerous.

The object of this invention is to so arrange a lamp of this kind thatall danger from the spark will be avoided. I accomplish this bysubmerging the points at which the connection is madein a transparentliquid not ignited by the spark. Glycerine is suitable for the purpose,it not being decomposed by the action of the current. The wires arepreferably electrically insulated with a substance impervious to theliquid-such as rubber-so that only the points at which contact is madeare exposed. The escape of electricity across from one conductor to theother at the exposed points will be quite inconsiderable.

A convenient form of 'my invention is shown in the accompanying drawing,whic is a view thereof in elevation.

A is an incandescing electric lamp placed in a Vessel, H, made entirelyof glass or having one or more glass sides, and filled with glycerine orother suitable liquid. The leading in wires or a of thelamp are formedinto hooks, as shown, which engage with. hooks b I) connected wit-l1 theconductors 12. Instead of two pairs of hooks, either pair could be ringsor eyes and the other hooks. A weight, 0, preferably a lead ring droppedover the neck of the lamp, is used to maintain good connection and tokeep the lamp in a vertical position. The wires, except the hooks,should be coated with an insulating substance impervious to the liquidused.

It will be seen that the lamp can be readily connected and disconnected,and that any spark produced thereby, being in liquid, will not be liableto ignite any gases, flour-dust, or other inflammable substance whichmight exist in the neighborhood.

Instead of keeping the connections constantly submerged in liquid, theymay be made and broken in a water-jar, but may be removed therefromafter being made, since no spark occurs, except on the making orbreaking of the circuit.

What I claim is- 1. An incandescing electric lamp the leading-in wiresof which are connected removably with the conducting-wires, the connections being submerged in liquid, substantially as set forth.

2. An incandescing electric lam-p the leading in Wires of which areconnected by hooks or books and eyes with the conducting-wires, suchhooks or hooks and eyes being submerged in liquid, and the wires beinginsulated, except at the points of contact, with a coating impervious tothe liquid, substantially asset forth.

This specification signed and witnessed this 9th day of June, 1882.

THOS. A. EDISON. WVitn esscs:

RIOHD. N. DYER, EDWARD H. PYATT.

